diff --git a/core/lib/Drupal/Core/Updater/Module.php b/core/lib/Drupal/Core/Updater/Module.php
index 06e1c1e..ac482d6 100644
--- a/core/lib/Drupal/Core/Updater/Module.php
+++ b/core/lib/Drupal/Core/Updater/Module.php
@@ -51,6 +51,16 @@ public function isInstalled() {
    * Implements Drupal\Core\Updater\UpdaterInterface::canUpdateDirectory().
    */
   public static function canUpdateDirectory($directory) {
+    $info_file = self::findInfoFile($directory);
+    $info = \Drupal::service('info_parser')->parse($info_file);
+    if (empty($info)) {
+      throw new UpdaterException(t('Unable to parse info file: %info_file.', array('%info_file' => $info_file)));
+    }
+
+    if (isset($info['type']) && $info['type'] == 'module') {
+      return FALSE;
+    }
+
     if (file_scan_directory($directory, '/.*\.module$/')) {
       return TRUE;
     }
diff --git a/core/lib/Drupal/Core/Updater/Theme.php b/core/lib/Drupal/Core/Updater/Theme.php
index b379325..6e95476 100644
--- a/core/lib/Drupal/Core/Updater/Theme.php
+++ b/core/lib/Drupal/Core/Updater/Theme.php
@@ -51,6 +51,16 @@ public function isInstalled() {
    * Implements Drupal\Core\Updater\UpdaterInterface::canUpdateDirectory().
    */
   static function canUpdateDirectory($directory) {
+    $info_file = self::findInfoFile($directory);
+    $info = \Drupal::service('info_parser')->parse($info_file);
+    if (empty($info)) {
+      throw new UpdaterException(t('Unable to parse info file: %info_file.', array('%info_file' => $info_file)));
+    }
+
+    if (isset($info['type']) && $info['type'] == 'theme') {
+      return FALSE;
+    }
+
     // This is a lousy test, but don't know how else to confirm it is a theme.
     if (file_scan_directory($directory, '/.*\.module$/')) {
       return FALSE;